S1 Corporation Board of Directors Rejects ACI Proposal

S1 Corporation SONE announced today that its Board of Directors, after thorough consideration and consultation with its legal and financial advisors, has rejected ACI Worldwide, Inc.'s ACIW previously announced proposal to acquire S1. The Board unanimously concluded that pursuing discussions with ACI at this time is not in the best financial or strategic interests of S1 and its stockholders. In doing so, the Board affirmed its commitment to S1's pending business combination with Fundtech.